I just got a new Supercede WS12 in Polarized 1.67 Grey with a back-side A/R. The first time I drove with them I immediately noticed significant luster (binocular interference). OK, time to adapt, right? Well, on closer inspection I discovered that the amount of polarization effect varies in different sections of the lens. I've never seen this in single vision jobs. I wonder if this a possible complication of all polarized progressives, or maybe just 1.67, or maybe just Freeforms, or even maybe just aspherics. The Supercede is a double aspheric design.
OD +0.25 sphere
OS Plano
+2.00 Add
PD 33/33.5
Came through with a 4.00 base and mounted in a 53/18 traditional full rim frame with a normal B dimension (not a sun frame or super wrap or oddball frame). Average lens thickness is 2.0 - 2.2mm.
The problem is best observed by waving the lenses horizontally (without torsion) in hand motion while observing a distant reflective surface through the lens. There is simply more polarization centrally than peripherally and it is observable in the top distance carrier portions as well as in the lower progressive zones, equally in both lenses. I removed the lenses from the frame to insure that they were not mounted too tightly and the observation was identical. The irregularity of the polarization was not similar to the mounting point distortion you'd expect to see in a lens that was simply mounted too tightly, either. I actually finished the job myself to be sure that the mounting was correct to eliminate such distortions.
Has anyone else experienced similar polarization irregularities in PALs? It renders the polarization virtually useless and I'm not sure yet how I'll proceed with the redo. I'm just glad it's me and not a patient! :)
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